Answer Happy

a) A wind turbine with power curve as shown in Figure 4a(i) is to be installed at a location with hub height annual wind speed distribution as per Figure 4a(ii). Estimate the percentage of time you will find the turbine blades not rotating. Calculate the annual energy production from this wind turbine if total loss in the balance of plant (BOP) is known to be 5 %. (5 marks) 3500 3000 2500 2000 Wind turbine power kW 1500 1000 500 0 0 2 10 12 20 22 24 26 28 30 32 16 18 Wind speed m/s Figure 4a(i) Wind turbine power curve
35 30 25 20 Occurrence 15 10 5 o 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Wind speed m/s Figure 4a(ii) Annual wind speed distribution
b) Describe and compare two major drivetrain designs for horizontal axis wind turbines. How does the drivetrain design affect other key components in the wind turbine? (5 marks) c) Explain how wind interacts with rotor blades of a horizontal axis wind turbine to convert wind energy to electricity. (5 marks) d) “Wind industry nowadays uses the Measure-Correlate-Predict (MCP) method to estimate the P50 wind speed at a specific site". What is your understanding about the MCP method? What is the meaning of P50 wind speed? (5 marks) (Total 20 marks)